SURFACE-MEMBRANE HYDROPHOBICITY OF PARAMECIUM-PRIMAURELIA MATING TYPES - ANALYSIS UNDER IMMATURITY AND MATURITY CONDITIONS

Paramecium primaurelia stock 90 clones were examined in their mating immaturity and maturity stages, under starving conditions triggering mating reactivity in mature cells. Living samples were labelled by cycloheptaamilose-dansyl chloride (CDC) complex, which has been proved to be an effective fluorescent marker of outer membrane proteins in living ciliates, as well as a sensitive probe towards microenvironment hydrophobicity. The analysis of CDC-labelled surface membrane region, usually engaged in conjugation, of immature and unpaired mature cells of mating types I and II, reveals differences in emission spectra, which can be referred to different hydrophobicity conditions. These findings lead us to assume that variations in surface membrane chemico-physical properties, differently affecting CDC fluorescence spectra, would be mating type-dependent and related to the functional states of cell immaturity or maturity, thus supporting the suggested role of hydrophobic interactions in Paramecium pair formation.